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101.
This article sets forth the main findings of an empirical study carried out among the main actors in the sector of large-scale retailing in Europe, as regards their respective practical experience incrm (Customer Relationship Management) as well as the opportunities offered by the Internet technologies in this field. The evidence collected is checked against the problems expounded in the literature hinging on the following four main questions: —the existence of national orientations that are taking shape in terms of the uses ofcrm —the reality of the training processes of companies leading to e-crm as well as the acquisition of the technical and organisational maturity necessary to master these tools —the variety of those uses and the issue of multichannelling —the relative benefits of market relationship linked to the development ofcrm procedures Thus this study offers an overview of emerging trends incrm peculiar to this sector. 相似文献
102.
The purpose of the present investigation was to systematically examine the effectiveness of the Sympson-Hetter technique and rotated content balancing relative to no exposure control and no content rotation conditions in a computerized adaptive testing system (CAT) based on the partial credit model. A series of simulated fixed and variable length CATs were run using two data sets generated to multiple content areas for three sizes of item pools. The 2 (exposure control) X 2 (content rotation) X 2 (test length) X 3 (item pool size) X 2 (data sets) yielded a total of 48 conditions. Results show that while both procedures can be used with no deleterious effect on measurement precision, the gains in exposure control, pool utilization, and item overlap appear quite modest. Difficulties involved with setting the exposure control parameters in small item pools make questionable the utility of the Sympson-Hetter technique with similar item pools. 相似文献
103.
In the present work, Pb(2+) and Cd(2+) adsorption onto a natural polysaccharide has been studied in membrane reactors. The process involves a stirred semi-batch reactor for the adsorption step and a microfiltration (MF) process in order to confine the particles. Due to their lower affinity for the biosorbent, Cd(2+) ions were found to breakthrough the process faster than Pb(2+) cations. The experimental results showed the technical feasibility of the pilot. A mass balance model based on the Langmuir equilibrium isotherm was used to describe the adsorption process. This relation is able to predict experimental data under different operating conditions: the adsorbent and metal concentrations, and the permeate flow rate. Based on these results, it is demonstrated that the biosorbent studied represents an interesting low-cost solution for the treatment of metal ions polluted waters. 相似文献
104.
Marchand B Douek PC Robert P Corot C Roux JP Adeleine P Hernandez-Hoyos M Cremillieux Y Orkisz M Canet E 《Magma (New York, N.Y.)》2002,14(3):259-267
Purpose To investigate the relative role of high resolution (spatial or temporal) magnetic resonance angiography (MRA) sequence and
of contrast agent properties in the evaluation of high-degree arterial stenosis.
Methods We qualitatively and quantitatively studied both 50 and 95% (300 μm diameter) stenosis of a 6 mm arterial phantom with two
contrast agents (CA), Gd-DOTA (r1 =2.9 mM−1 s−1) versus P760 (r1 =25 mM−1 s−1) at several CA concentrations, including arterial peak concentration after injection of either a single or double dose of
CA, using either a high temporal (booster) or high spatial (HR) resolution 3D MRA sequences. Experimental data were then compared
to theoretical data.
Results With the 3D HR sequence, both visual and quantitative analysis were significantly better compared to the 3D booster sequence,
at each phantom diameter. Quantitative analysis was significantly improved by injection of a double versus a single dose of
each CA (Gd-DOTA or P760), primarily in high degree stenosis.
Conclusion Combined MRA spatial resolution and high CA efficiency are mandatory to correctly evaluate high degree stenosis. 相似文献
105.
This study examines the development of children's ability to express emotions in their human figure drawing. Sixty children of 5, 8, and 11 years were asked to draw "a man," and then a "sad", "happy," "angry" and "surprised" man. Expressivity of the drawings was assessed by means of two procedures: a limited choice and a free labelling procedure. Emotionally expressive drawings were then evaluated in terms of the number and the type of graphic cues that were used to express emotion. It was found that children are able to depict happiness and sadness at 8, anger and surprise at 11. With age, children use increasingly numerous and complex graphic cues for each emotion (i.e., facial expression, body position, and contextual cues). Graphic cues for facial expression (e.g., concave mouth, curved eyebrows, wide opened eyes) share strong similarities with specific "action units" described by Ekman and Friesen (1978) in their Facial Action Coding System. Children's ability to depict emotion in their human figure drawing is discussed in relation to perceptual, conceptual, and graphic abilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
Zhou Qing; Hofer Claire; Eisenberg Nancy; Reiser Mark; Spinrad Tracy L.; Fabes Richard A. 《Canadian Metallurgical Quarterly》2007,43(2):369
The developmental trajectories of attention focusing (by parents' and teachers' reports) and attentional and behavioral persistence (observed during a laboratory task)--2 indexes of effortful control--and externalizing problems from ages 5 to 10 years were examined for 356 children combined from a pair of 3-wave (2 years apart) longitudinal studies. The authors identified clusters of children with distinct trajectories for these variables and examined the links between the effortful control trajectories and the externalizing problem trajectories. Although attention focusing remained relatively stable, attentional and behavioral persistence continued to show mean-level changes (especially among the children with lower levels of persistence). Children with high and stable trajectories of effortful control tended to exhibit low and stable trajectories of externalizing problems, whereas those with lower and/or less stable trajectories of effortful control showed more elevated and/or fluctuating trajectories of externalizing problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
Sebastien Narses Faten Sadaka Claire‐Hélène Brachais Jean‐Pierre Couvercelle 《应用聚合物科学杂志》2013,129(5):2891-2904
The coloration of different polymer films (from commodity and packaging films to performance films) by contact with various food coloring substances was evaluated. For this purpose, both solubility parameters as a prediction tool, and immersion experiments for time range between 24 and 1000 h were established. The two predicting tools are the Hoy and Hoftyzer‐Van Krevelen (HVK) methods. For PE and PP, HVK's method is preferred for predicting coloration. Neither of the HVK's and Hoy's methods was able to establish a coloration prediction for PET while both methods could predict the staining of PEEK. The coloration of partially and fully fluorinated polymers is well predicted by the Hoy's method. The behavior of PP/PA and PP/PA/PP multilayer films was also studied. Crystallinity degree of polymers, temperature and concentration of coloring molecules are also important parameters, which are not taken into account in solubility theories. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
108.
109.
Christian Gumpenberger Juan Gorraiz Martin Wieland Ivana Roche Edgar Schiebel Dominique Besagni Claire François 《Scientometrics》2013,95(1):277-297
Negative results are not popular to disseminate. However, their publication would help to save resources and foster scientific communication. This study analysed the bibliometric and semantic nature of negative results publications. The Journal of Negative Results in Biomedicine (JNRBM) was used as a role model. Its complete articles from 2002–2009 were extracted from SCOPUS and supplemented by related records. Complementary negative results records were retrieved from Web of Science in “Biochemistry” and “Telecommunications”. Applied bibliometrics comprised of co-author and co-affiliation analysis and a citation impact profile. Bibliometrics showed that authorship is widely spread. A specific community for the publication of negative results in devoted literature is non-existent. Neither co-author nor co-affiliation analysis indicated strong interconnectivities. JNRBM articles are cited by a broad spectrum of journals rather than by specific titles. Devoted negative results journals like JNRBM have a rather low impact measured by the number of received citations. On the other hand, only one-third of the publications remain uncited, corroborating their importance for the scientific community. The semantic analysis relies on negative expressions manually identified in JNRBM article titles and abstracts and extracted to syntactic patterns. By using a Natural Language Processing tool these patterns are then employed to detect their occurrences in the multidisciplinary bibliographical database PASCAL. The translation of manually identified negation patterns to syntactic patterns and their application to multidisciplinary bibliographic databases (PASCAL, Web of Science) proved to be a successful method to retrieve even hidden negative results. There is proof that negative results are not only restricted to the biomedical domain. Interestingly a high percentage of the so far identified negative results papers were funded and therefore needed to be published. Thus policies that explicitly encourage or even mandate the publication of negative results could probably bring about a shift in the current scientific communication behaviour. 相似文献
110.
Dush Claire M. Kamp; Kotila Letitia E.; Schoppe-Sullivan Sarah J. 《Canadian Metallurgical Quarterly》2011,25(3):356
Supportive coparenting after relationship dissolution is associated with increased father involvement which can buffer against the negative effects of parental relationship dissolution. Low-income, at-risk families are much more likely to experience relationship dissolutions; hence, supportive coparenting after dissolution is particularly important in these families. We examined whether relationship (commitment and quality) and child (difficult temperament and gender) characteristics predicted initial levels of, and change in, supportive coparenting after relationship dissolution in the Fragile Families and Child Wellbeing Study (N = 1,603). We used structural equation modeling of latent growth curves to examine four time points collected at the focal child's birth and first, third, and fifth birthdays. Ninety-percent of the mothers had nonmarital births, and about three-quarters had a high school diploma or less education. Overall, supportive coparenting decreased over time. Mothers in more committed relationships prior to the dissolution initially had significantly lower supportive coparenting. But over time, mothers who had been in more committed relationships increased in supportive coparenting. Mothers who had been in higher quality relationships prior to dissolution initially reported more supportive coparenting. At each time point, if a mother was romantically involved with a new partner, she reported significantly lower supportive coparenting compared to mothers who were single. With regard to child characteristics, mothers who reported their child as more difficult had significantly lower initial supportive coparenting. Similar results for fathers are discussed. Overall, the relationship characteristics of parents were important predictors of supportive coparenting both initially and over time. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献